One of the most common failure points where water enters a building's envelope is around windows and doors. Water penetration is one of the most significant factors leading to premature failures of structures. Most windows and doors, whether aluminum or vinyl, are secured in the rough opening by a nailing flange. As an example, the window is placed in the rough opening from the outside and secured using nail fasteners that are driven through the window's nailing flange. Installation methods vary significantly and range from as little as building paper lapping over or under the window flange to flashing materials being shingled in the rough opening prior to window installation, application of caulking installed from a tube caulk gun under the window flange and various flashing or adhesive tapes applied over the window flange. Installation is often performed from ladders or scaffolding at various levels above the ground. Flashing materials are often misaligned or applied in an inconsistent manner that leaves wrinkles or voids in the material leading to leaks, i.e., direct water pathways to the underlying building materials. The flashing is assembled from numerous separate components that when installed cover each other making inspection of the completed flashing assembly extremely difficult. Further, since there is often a time lapse between installation of the various components they are often damaged by wind, rain or other mechanical disturbances.
Given these problems, there is a need for an improved method of ensuring a weather-tight barrier for window installations.